Proportion and risk factors of zonulopathy in patients with age-related cataract.

Purpose: To investigate the proportion of zonulopathy in patients with age-related cataract, and further explore demographics and ocular characteristics, as well as potential risk factors. Methods: Hospital-based, observational, cross-sectional study. We enrolled consecutive patients who were 45 years or older and diagnosed with age-related cataract and underwent surgery between October 2022 and April 2023 at the Division of Cataract, Beijing Tongren Hospital. Zonulopathy was diagnosed based on intraoperative signs. We calculated the total proportion, age, and gender specific proportions of zonulopathy. We compared the demographic and ocular characteristics between the cases with and without zonulopathy. Univariate and multivariate logistic regression analyses were employed to determine the risk factors associated with the presence of zonulopathy in patients with age-related cataract. Results: A total of 640 age-related cataract patients with a median age of 70.0 (64.0-77.0) were enrolled. Zonulopathy was diagnosed intraoperatively in 70 patients (10.9%). Compared with the patients having no zonulopathy, those with zonulopathy were likely to be older (P < 0.001), have a shallower central ACD (P < 0.001), a thicker lens (P < 0.001) and a shorter AL (P = 0.010). Logistic regression analyses showed that the risk predictors associated with the presence of zonulopathy in patients with age-related cataract were older age (OR, 1.042; P = 0.035) and shallower central ACD (OR, 0.834; P < 0.001). Conclusion: Zonulopathy in age-related cataract patients is not an uncommon finding. Clinicians should be mindful of zonulopathy in patient population with advanced age and shallower ACD.

Zonulopathy Identified During Cataract Extraction in Patients With Primary Angle Closure Disease.

PRCIS: The proportion, clinical characteristics, and risk factors of zonulopathy in primary angle closure disease (PACD) were analyzed. Zonulopathy is an underrecognized common finding in PACD, especially in patients with acute angle closure (AAC). PURPOSE: To examine the proportion and risk factors associated with intraoperative zonulopathy in PACD. PATIENTS AND METHODS: This is a retrospective analysis of 88 consecutive patients with PACD who underwent bilateral cataract extraction at Beijing Tongren Hospital from August 1, 2020 to August 1, 2022. Zonulopathy was diagnosed based on intraoperative findings including the presence of a lens equator, radial folds of the anterior capsule while making capsulorhexis, and other signs of the unstable capsular bag. The subjects were grouped based on their PACD subtype diagnoses: AAC, primary angle closure glaucoma (PACG), primary angle closure (PAC), or primary angle closure suspect (PACS). Multivariate logistic regression was performed to identify risk factors associated with zonulopathy. The proportion and the risk factors of zonulopathy were estimated in patients with PACD and in PACD subtypes. RESULTS: Of 88 patients with PACD (67.3 ± 6.9 y old, 19 males and 69 females), the overall proportion of zonulopathy was 45.5% of patients (40/88) and 30.1% of eyes (53/176). Among the PACD subtypes, the proportion of zonulopathy was highest (69.0%) in AAC, followed by 39.1% in PACG, and 15.3% in PAC and PACS combined. AAC was an independent risk factor associated with zonulopathy ( P = 0.015, AAC vs PACG, PAC, and PACS combined; odds ratio: 0.340, CI: 0.142-0.814). Shallower anterior chamber depth ( P = 0.031) and greater lens thickness ( P = 0.036), but not laser iridotomy, were associated with an increased proportion of zonulopathy. CONCLUSIONS: Zonulopathy is common in PACD, especially in patients with AAC. Shallow anterior chamber depth and thick lens thickness were associated with an increased proportion of zonulopathy.

Low-dose transscleral cyclophotocoagulation with subsequent phacoemulsification in the treatment of prolonged acute primary angle closure.

BACKGROUND: To explore the outcomes and mechanisms of intraocular pressure (IOP) control using low-dose transscleral cyclophotocoagulation (LDTSCP) followed by phacoemulsification in patients with prolonged acute primary angle closure (APAC). METHODS: Patients with prolonged APAC refractory to all other treatment modalities were prospectively recruited, and underwent LDTSCP (10 shots, 2 s duration, 120° treatment with the energy starting at 1500 mW and titrated to the level with audible burst but not exceeding 2000 mW) and anterior chamber paracentesis 1 week prior to phacoemulsification with intraocular lens implantation and viscogoniosynechiolysis. Postoperative IOP, vision, anatomic changes on anterior segment optical coherence tomography and complications were recorded. RESULTS: Twenty eyes with prolonged APAC were recruited. Median follow-up was 12 months (range 9-18), at which point the vision in all eyes had improved and IOP was ≤17 mm Hg on no antiglaucoma medications. Following LDTSCP at postoperative day (POD) 1, IOP decreased in all eyes to a median 15 mm Hg (range: 6-28 mm Hg). Post-LDTSCP supraciliary effusion (SCE) occurred in 90% of eyes on POD1 or POD7 and ciliary body defect (CBD) was detected in 30% of eyes and resolved in all cases by postoperative month 1. Lower post-LDTSCP IOP was associated with more number of bursts (r=-0.558, p=0.011) and higher grade of SCE (r=-0.877, p<0.001), but not with total energy (p=0.240). Eyes with CBD (p=0.018) and a higher number of bursts (r=0.657, p=0.002) had higher grade SCE. CONCLUSIONS: LDTSCP-induced SCE may explain the post-LDTSCP IOP reduction seen in eyes with prolonged APAC. LDTSCP instead of traditional more extensive treatment, was sufficient to provide a relatively safe and effective bridge therapy prior to phacoemulsification. TRIAL REGISTRATION NUMBER: Chinese Clinical Trials Registry (ChiCTR1900023567).

Oncocytic Carcinoma in the Retromolar Trigone: A Case Report.

Oncocytic carcinoma (OC) is a pretty rare malignant neoplasm. Oncocytic carcinomas mainly occur in major salivary glands but infrequently occur in minor salivary glands. We report a case of OC occurring in the retromolar glands involving the ipsilateral tonsil, which has not been reported in the English literature. This case may expand the database of OC, and provide diagnosis and treatment ideas for clinicians.

DNA-based qualitative and quantitative identification of bovine whey powder in goat dairy products.

As one of the main ingredients in some milk powders, whey powder is sometimes added to pure goat milk products, which can cause health risks, economic fraud, and unfair competition of food industries. This study is the first to explore qualitative and quantitative methods to identify adulteration of bovine whey powder in goat dairy products based on DNA. We extracted DNA from whey powder using a modified DNA extraction method; this exhibited good quality and integrity, with purity of 1.53 to 1.75 and concentration of 122 to 179 ng/µL. Conventional PCR and real-time PCR were compared for qualitative detection of bovine whey powder; real-time PCR demonstrated sensitivity of 0.01 ng/µL, which was higher than the 0.05 ng/µL detected by the conventional PCR method. Furthermore, real-time PCR was conducted for DNA quantitative detection, with good linearity (R2 = 0.9858) obtained for bovine whey powder contents from 0.1% to 30%. Relative error decreased with increase of the mixing proportion of whey powder; the coefficient of variation above 0.1% of the mixing ratio was close to or less than 5%; and the relative standard deviation of repeatability results was less than 5%. Considering the economic costs of testing, conventional PCR could be performed first, and samples with obvious intentional adulteration detected can be further accurately quantified by real-time PCR. Overall, this research provides a realistic and effective method for qualitative and quantitative identification of bovine whey powder in goat dairy products, thus laying a good foundation for verification of goat dairy product label claims and industrial control.

Construction of a BMP-2 gene delivery system for polyetheretherketone bone implant material and its effect on bone formation in vitro.

Polyetheretherketone (PEEK) has been widely investigated for improving its biological inert to enable it to achieve stronger osteogenic capability and to be a promising material in implant fields. The most important mechanism that makes a successful implantation is osteointegration. Surface modification is an appropriate method to maintain the excellent mechanical properties of PEEK and simultaneously endow PEEK certain biological characters. In this work, we attempted to shape the nano-topography of PEEK surface by nitrogen low-temperature plasma and polydopamine coating on the surface as a secondary reaction platform to bond the aminated poly (lactic-co-glycolic acid) (PLGA) microspheres encapsulating the BMP-2 gene for enhancing the biological activity. Scanning electron microscope, atomic force microscopy, X-ray photoelectron spectroscopy and water contact angle (CA) measurements were applied to characterize the surface of modified or untreated PEEK. Surface characterization showed that the modification was successfully performed on PEEK including a rougher and more hydrophilic surface with nanotopographic features. The influence on cell adhesion, proliferation and differentiation was evaluated by culturing of rat bone marrow mesenchymal stem cells on different modified PEEK substrates in vitro. The biological results indicated that the low-temperature plasma treatment and PDA-coating on PEEK significantly promoted cell adhesion and proliferation. And the osteogenic differentiation was effectively improved by BMP-2 gene releasing from PLGA-NH2 microspheres. The results showed that this novel biological surface modification endowed PEEK with outstanding bioactivity and osteogenic ability, providing a theoretical basis for application in the field of implantation.

Changing Trends in Glaucoma Surgery Over the Past 5 Years in China.

PURPOSE: To analyze the trends of glaucoma surgery procedures over the past 5 years among hospitals across major provinces in China. MATERIALS AND METHODS: This was a retrospective observational study based on medical records. We obtained the annual numbers of commonly performed glaucoma incisional surgeries from 57 hospitals of 30 provincial regions in the Chinese Glaucoma Study Consortium (CGSC) from January 2015 to September 2019. The trend of glaucoma surgery was analyzed by Cochrane-Armitage trend test. RESULTS: Trabeculectomy, cataract extraction combined with goniosynechialysis, cataract extraction combined with trabeculectomy, and surgical peripheral iridotomy (SPI) were the top 4 surgical procedures percentages of which have the most substantial change over the course of 2015 to 2019 (all Ptrend <0.001). Numbers of trabeculectomies decreased significantly from 47.59% in 2015 to 31.21% in 2019; cataract extraction combined with goniosynechialysis increased from 12.12% to 28.48%; cataract extraction combined with trabeculectomy increased from 13.11% to 15.97%; and SPI decreased from 9.03% to 6.34%. The proportion of internal drainage surgery increased from 24.31% in 2015 to 39.29% in 2019 while external drainage surgery decreased from 69.20% to 54.64% (All Ptrend <0.001). The microinvasive glaucoma surgeries including AB-interno Canaloplasty, gonioscopy-assisted transluminal trabeculotomy, and Trabectome, increased from 0.62% to 1.40% (Ptrend<0.001). Across all study hospitals, the trends were similar, except for the Tibet Autonomous Region Eye Center, where SPI and trabeculectomy remained the most common anti-glaucoma surgeries. CONCLUSION: In the past 5 years, we observed substantial reduction in trabeculectomy, and increase in combination cataract-glaucoma procedures across major hospitals in China. The proportion of internal drainage surgery increased, while external drainage surgery decreased significantly. Detailed understanding of shifting trends in glaucoma surgeries can facilitate better health care resource allocation and training of glaucoma subspecialists in China.

SNHG17/miR-384/ELF1 axis promotes cell growth by transcriptional regulation of CTNNB1 to activate Wnt/ß-catenin pathway in oral squamous cell carcinoma.

Increasing evidence proved the abnormal expression of long non-coding RNAs (lncRNAs) in various human malignancies, including oral squamous cell carcinoma (OSCC). Nevertheless, limited explorations concern the role of lncRNA small nucleolar RNA host gene 17 (SNHG17) in OSCC. Herein, SNHG17 was disclosed to be remarkably upregulated in OSCC cell lines and promoted OSCC cell growth. Further mechanistic studies, including DNA/RNA pull down, RIP, ChIP, and luciferase reporter gene assays, were conducted. It was confirmed that Wnt/ß-catenin signaling pathway was involved in the SNHG17-mediated OSCC cell growth. Moreover, E74 like ETS transcription factor 1 (ELF1) was identified as the transcription activator of CTNNB1 (ß-catenin mRNA) in OSCC. Inspired by competing for endogenous RNAs (ceRNAs) network, we were pleasantly surprised to find that SNHG17 and ELF1 functioned as ceRNAs in OSCC via competitively binding to microRNA-384 (miR-384). By using rescue assays, we revealed that SNHG17 facilitated OSCC cell growth through modulating miR-384/ELF1 axis. Importantly, we certified that ELF1 was indispensable for SNHG17-affected OSCC progression. Collectively, it can be concluded that SNHG17/miR-384/ELF1 axis contributed to OSCC cell growth via promoting CTNNB1 expression, thus activating Wnt/ß-catenin signaling pathway.

[Research progress on the effect of surface charge of biomaterials on bone formation].

With the continuous progress of materials science and biology, the significance of biomaterials with dual characteristics of materials science and biology is keeping on increasing. Nowadays, more and more biomaterials are being used in tissue engineering, pharmaceutical engineering and regenerative medicine. In repairing bone defects caused by trauma, tumor invasion, congenital malformation and other factors, a variety of biomaterials have emerged with different characteristics, such as surface charge, surface wettability, surface composition, immune regulation and so on, leading to significant differences in repair effects. This paper mainly discusses the influence of surface charge of biomaterials on bone formation and the methods of introducing surface charge, aiming to promote bone formation by changing the charge distribution on the surface of the biomaterials to serve the clinical treatment better.

Screening of frozen-thawed conditions for keeping nutritive compositions and physicochemical characteristics of goat milk.

Frozen milk can help producers overcome the seasonality of goat milk production, low goat production and short lactation periods, and avoid discarding milk during some special periods. We investigated effects of combination between freezing (cryogenic refrigerator of -16 to -20°C or ultra-cryogenic refrigerator of -76 to -80°C) and thawing (homeothermy of 20 to 25°C or refrigeration of 2 to 4°C) on nutritive compositions and physicochemical characteristics of raw goat milk during storage period (80 d). Compared with fresh goat milk, the frozen-thawed milk decreased contents of fat, protein, and lactose, as well as surface tension and stability coefficient, whereas increased effective diameter and polydispersity index. The average values of color values (L*, a*, and b*) in 4 group samples changed from 83.01 to 82.25, -1.40 to -1.54, 3.51 to 3.81, respectively, and the ΔE of most samples did not exceed 2. In contrast to the other 3 frozen-thawed treatments, goat milk treated with ultra-cryogenic freezing-homeothermic thawing (UFHT) possessed higher fat (5.20 g/100 g), smaller effective particle diameter (0.32 µm), and the lowest polydispersity index value (0.26). The color and confocal laser scanning microscopy images of UFHT were similar to those of fresh goat milk, illustrating UFHT was the optimal approach to maintain the natural quality of goat milk. Our finding provides a theoretical basis for producers to freeze surplus milk.

Heterozygous PAX6 mutations may lead to hyper-proinsulinaemia and glucose intolerance: A case-control study in families with congenital aniridia.

AIM: PAX6 is a transcription factor involved in embryonic development of many organs, including the eyes and the pancreas. Mutations of PAX6 gene is the main cause of a rare disease, congenital aniridia (CA). This case-control study aims to investigate the effects of PAX6 mutations on glucose metabolism and insulin secretion in families with CA. METHODS: In all, 21 families with CA were screened by Sanger sequencing. Patients with PAX6 mutations and CA (cases) and age-matched healthy family members (controls) were enrolled. Oral glucose tolerance test (OGTT) was performed to detect diabetes or impaired glucose tolerance (IGT). Insulin and proinsulin secretion were evaluated. RESULTS: Among 21 CA families, heterozygous PAX6 mutations were detected in five families. Among cases (n = 10) from the five families, two were diagnosed with newly identified diabetes and another two were diagnosed with IGT. Among controls (n = 12), two had IGT. The levels of haemoglobin A1c were 36 ± 4 mmol/mol (5.57 ± 0.46%) and 32 ± 5 mmol/L (5.21 ± 0.54%) in the cases and the controls, respectively (p = 0.049). More importantly, levels of proinsulin in the cases were significantly higher than that of the controls, despite similar levels of total insulin. The areas under the curve of proinsulin in the cases (6425 ± 4390) were significantly higher than that of the controls (3709 ± 1769) (p = 0.032). CONCLUSION: PAX6 may participate in the production of proinsulin to insulin and heterozygous PAX6 mutations may be associated with glucose metabolism in CA patients.

Coding Variants in HOOK2 and GTPBP3 May Contribute to Risk of Primary Angle Closure Glaucoma.

Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. This study proposed to screen candidate PACG-associated variants in Chinese Han people. Whole exome sequencing was applied to five confirmed PACG patients and two primary angle closure suspect individuals within a PACG-enriched Chinese Han family. A series of bioinformatics analyses were implemented to obtain high-risk single nucleotide variant (SNV) loci for PACG, which were subsequently used for linkage analysis for identifying linkage genome regions. In addition, MassARRAY SNV genotyping was applied to high-risk PACG loci as well as those within linkage regions in another independent cohort including 251 PACG and 251 normal samples to further screen high-confidence SNVs. A total of 27 loci in 19 genes remained after linkage analysis. The 19 genes were significantly enriched in biological processes tightly related to PACG, including retinol metabolism and salmonella infection. Two nonsynonymous SNV loci, rs897804 in exon15 of HOOK2 and rs3745193 in exon7 of GTPBP3, were recognized with higher variant frequency in PACG samples than that in control samples after association analysis of MassARRAY SNV genotyping data. This study sheds new light on the understanding of PACG incidence among Chinese Han people.

The Chinese Glaucoma Study Consortium for Patients With Glaucoma: Design, Rationale and Baseline Patient Characteristics.

PRECIS: Chinese Glaucoma Study Consortium (CGSC) as the first nationwide glaucoma registry in China, we describe its design, rationale, the geographic distribution of the hospitals, and baseline patient characteristics. AIM: As a leading cause of blindness in China, glaucoma affects 2% to 4% of adults over the age of 40 and will become increasingly prevalent as the population ages. At the national level, there are few reports on the current medical practice for glaucoma patients. CGSC will be considered as the first nationwide glaucoma registry in China. Here we describe its design, rationale, the geographic distribution of the hospitals, and baseline patient characteristics. METHODS: From December 21, 2015 to September 9, 2018, CGSC recruited patients with the diagnoses of primary angle-closure suspect, primary angle-closure, primary angle-closure glaucoma, acute primary angle closure, primary open-angle glaucoma (POAG), pigmentary glaucoma (PG), and pseudoexfoliative glaucoma (PXG) from 111 hospitals covering 67 cities from 22 provinces, 4 municipalities, and 5 autonomous regions in mainland China. Clinical data were collected using an Electronic Data Capture System designed by Tongren hospital and Gauss informed Ltd. Blood samples were collected from every patient for further genetic analysis. RESULTS: Medical records of 10,892 patients were collected, of which 5762 patients have complete information. The average age of those with complete information (n=5762) was 62.05±11.26 years old, and 35.25% were males. Primary angle-closure disease, including primary angle-closure suspect/primary angle-closure/primary angle-closure glaucoma/acute primary angle closure, was predominant (4588, 79.63%), and the distribution for others is as follows: POAG (1116, 19.37%), PXG (41, 0.71%) and PG (17, 0.30%). A total of 16,684 blood samples were collected, of which 9917 (82.68%) were primary angle-closure disease, 1987 (16.57%) were POAG, 69 (0.58%) were PXG, 22 (0.18%) were PG, and 4689 were normal controls. CONCLUSIONS: The CGSC is the first national-level glaucoma registry study in China. Clinical data and blood samples will provide the opportunity to study the epidemiology of glaucoma in Chinese hospitals, to evaluate the level of medical diagnosis and treatment of glaucoma in China, and to identify the susceptibility loci for glaucoma.

Development and Validation of a Deep Learning System to Detect Glaucomatous Optic Neuropathy Using Fundus Photographs.

Importance: A deep learning system (DLS) that could automatically detect glaucomatous optic neuropathy (GON) with high sensitivity and specificity could expedite screening for GON. Objective: To establish a DLS for detection of GON using retinal fundus images and glaucoma diagnosis with convoluted neural networks (GD-CNN) that has the ability to be generalized across populations. Design, Setting, and Participants: In this cross-sectional study, a DLS for the classification of GON was developed for automated classification of GON using retinal fundus images obtained from the Chinese Glaucoma Study Alliance, the Handan Eye Study, and online databases. The researchers selected 241 032 images were selected as the training data set. The images were entered into the databases on June 9, 2009, obtained on July 11, 2018, and analyses were performed on December 15, 2018. The generalization of the DLS was tested in several validation data sets, which allowed assessment of the DLS in a clinical setting without exclusions, testing against variable image quality based on fundus photographs obtained from websites, evaluation in a population-based study that reflects a natural distribution of patients with glaucoma within the cohort and an additive data set that has a diverse ethnic distribution. An online learning system was established to transfer the trained and validated DLS to generalize the results with fundus images from new sources. To better understand the DLS decision-making process, a prediction visualization test was performed that identified regions of the fundus images utilized by the DLS for diagnosis. Exposures: Use of a deep learning system. Main Outcomes and Measures: Area under the receiver operating characteristics curve (AUC), sensitivity and specificity for DLS with reference to professional graders. Results: From a total of 274 413 fundus images initially obtained from CGSA, 269 601 images passed initial image quality review and were graded for GON. A total of 241 032 images (definite GON 29 865 [12.4%], probable GON 11 046 [4.6%], unlikely GON 200 121 [83%]) from 68 013 patients were selected using random sampling to train the GD-CNN model. Validation and evaluation of the GD-CNN model was assessed using the remaining 28 569 images from CGSA. The AUC of the GD-CNN model in primary local validation data sets was 0.996 (95% CI, 0.995-0.998), with sensitivity of 96.2% and specificity of 97.7%. The most common reason for both false-negative and false-positive grading by GD-CNN (51 of 119 [46.3%] and 191 of 588 [32.3%]) and manual grading (50 of 113 [44.2%] and 183 of 538 [34.0%]) was pathologic or high myopia. Conclusions and Relevance: Application of GD-CNN to fundus images from different settings and varying image quality demonstrated a high sensitivity, specificity, and generalizability for detecting GON. These findings suggest that automated DLS could enhance current screening programs in a cost-effective and time-efficient manner.

Mucoepidermoid carcinoma arising in Warthin’s tumor of the upper lip: a case report and review / 口腔疾病防治

Objective @#To provide a reference for the diagnosis and treatment of mucoepidermoid carcinoma arising in Warthin’s tumor of the lip by investigating the diagnosis, treatment and prognosis of the disease.@*Methods @# A case of mucoepidermoid carcinoma arising in Warthin’s tumor of lip was reported, including the clinical manifestation, treatment, pathological characteristics and prognosis. The related literature was also reviewed and analyzed.@*Results@# A painless mass on the left lip lasting more than one month was found. Resection of the left lip was performed. Pathological examination showed that the tumor was a hybridoma composed of mucoepidermoid carcinoma and Warthin’s tumor. There was no recurrence or distant metastasis after 34 months. To date, this type of disease has been rarely reported. After thorough resection, the prognosis and survival rate are promising in most cases, with no recurrence or metastasis.@*Conclusion@#Mucoepidermoid carcinoma in Warthin’s tumor of the lip is rare. Clinical manifestations, imaging features and histological examination are useful when diagnosing the disease. Thorough resection will reduce the risk of disease recurrence.

Mandibular Gorham-Stout disease: A case report and literature review.

RATIONALE: Gorham-Stout disease (GSD) is characterized by aggressive bone resorption, proliferation of vascular or lymphatic vessels, and soft-tissue swelling. Bones that initially appear normal start to resorb, partially or completely. However, the etiology of GSD is unknown. PATIENT CONCERNS: A 29-year-old man with a chief complaint of toothache and mobility in the lower right mandible for the previous 1 year. DIAGNOSES: Gorham-Stout disease (GSD). INTERVENTIONS: The RANK-ligand inhibitor denosumab was suggested to use to inhibit the development of osteoclasts and slow mandibular resorption. In addition, we proposed resection of the remaining mandible and reconstruction via vascularized bone graft, after resorption of the mandible had become stationary. OUTCOMES: Regular follow-ups were advised to this patient to monitor the stability of bone resorption prior to any surgical intervention. LESSONS: We strongly recommend that every attempt should be made for early diagnosis and prompt effective medical and surgical management. The failure to do so results in further complications and poor prognosis.

Sequence-Modulated Interactions between Single Multivalent DNA-Conjugated Gold Nanoparticles.

DNA-conjugated gold nanoparticle (AuNP) is an attractive building block to construct elegant plasmonic nanomaterials by self-assembly but the complicated interaction between multivalent nanoconjugates governing the assembly process and the properties of assembled structures remains poorly understood. Herein, with an in situ kinetic single-particle imaging method, we report the dynamic interaction between single multivalent DNA-conjugated AuNPs quantitatively depends on the nucleic acid sequence in nanoconjugates. From the binding dynamics analysis, it was found that the binding of nanoconjugates with DNA length longer than nine bases is kinetically irreversible and the binding rate is dependent on both the sequence length and GC content, enabling us to predict the rational modulation of binding rates of individual building blocks for stepwise assembly. Moreover, the reversibility for the multivalent interaction between single nanoconjugates at constant temperature can be reinstated by adopting the DNA sequence with single-nucleotide mismatch and the lifetime for nanoconjugates at bound state can be tailored by changing the mismatch positions in DNA strands, providing new opportunity to create active nanostructures with controlled dynamic properties. All these findings provide new insights for understanding the multivalent interaction during the assembly process at the single-nanoconjugate level and predicting the programmable self-assembly of engineered nanoconjugates for the fabrication of dynamic nanomaterials.

Single Plasmonic Nanosprings for Visualizing Reactive-Oxygen-Species-Activated Localized Mechanical Force Transduction in Live Cells.

Mechanical force signaling in cells has been regarded as the biological foundation of various important physiological functions. To understand the nature of these biological and physiological processes, imaging and determining the mechanical signal transduction dynamics in live cells are required. Herein, we proposed a strategy to determine mechanical force as well as its changes with single-particle dark-field spectral microscopy by using a single plasmonic nanospring as a mechanical sensor, which can transfer force-induced molecular extension/compression into spectral responses. With this robust plasmonic nanospring, we achieved the visualization of activation of localized mechanical force transduction in single live cells triggered by reactive-oxygen-species (ROS) stimulation. The successful demonstration of a biochemical ROS signal to mechanical signal conversion suggested this strategy is promising for studying mechanical force signaling and regulation in live biological systems.